Sentence Correction

An analyst advised the company to invest $6 million into further development, a recommendation that could result in more spending by the construction company on its own equipment and decreasing the dependence on other companies to supply machinery.

Part A - "more spending by the construction company on its own equipment" == a gerund phrase. Here 'spending' is a GERNUND
Part B - "decreasing the dependence on other companies to supply machinery" == a participial phrase. Here 'decreasing' is a PARTICIPLE

Its understandable from 'could result in more spending...equipment' that SPENDING is a part of the prepositional phrase "in spending...equipment" ie taking the noun position so SPENDING is a GERUND here

But in 'could result in decreasing the ...machinery' ==> even though decreasing is part of prepositional phrase starting with 'in'...its a PARTICIPLE here not aGERUND. WHY????
Pls help.

Thanks
Patanjali